Gouache is a type of water-medium paint that is designed to be opaque. It consists of natural pigment, water, a binding agent (usually gum arabic or dextrin), and sometimes additional inert material. Gouache is similar to watercolor in that it can be rewetted and dried to a matte finish, and the paint can become infused into its paper support. However, it is normally used in an opaque painting style and can form a superficial layer, similar to acrylic or oil paints. Gouache is often described as "opaque watercolor" and is used by commercial artists for works such as posters, illustrations, comics, and for other design work. It is also used in cinema and animation for concepts and backgrounds. Gouache has a paste-like consistency and may need to be diluted with water before use. It is often applied with an airbrush. Unlike acrylic, gouache is not waterproof when dry.